1.編輯/etc/gdm/custom.conf爲如下：
# GDM configuration storage
[daemon]
AutomaticLoginEnable=true
AutomaticLogin=root
#TimedLoginEnable=true
#TimeLogin=root
#TimeLogDelay=7
[security]
[xdmcp]
[chooser]
[debug]
# Uncomment the line below to turn on debugging
#Enable=true
2.init 6 (重啓OS)